This invention is directed to triazole/arylamine-modified sulfonates as multifunctional lubricant additives and to lubricant compositions containing same.
Metallic aryl sulfonates such as calcium dinonylnaphthalene sulfonates have been widely used in petroleum and synthetic lubricants as rust and corrosion inhibiting additives. Additionally, these and related metallic aryl sulfonates have, on occasion, provided good detergency and demulsibility properties in a variety of lubricant formulations.
Lubricant in service applications often generate acid species or acid-forming species, especially when exposed to high operating temperatures, extended service life and/or contact with atmospheric oxygen during aeration caused by churning or moving elements of the lubricated machine. Acid-forming species can also be formed via hydrolysis, thermal decomposition, or other similar mechanisms.
If metallic arylsulfonates are used as additives in such systems described above, neutralization or acidification to form sulfonic acids can occur. If both metallic aryl sulfonates and aryltriazoles or arylamines are used together in a lubricant, or alternatively pre-reacted, these arylsulfonic acids and aryltriazoles or arylamines can react to form sulfonamides or sulfonium salts.